With the development of industry and human activities, a large amount of metal ions are released. Many of these metal ions, such as cadmium, chromium, mercury, are enriched in the food chain and often cause many hazards to local ecosystems and human health. This project will establish a broader and cheaper rapid detection technology to reduce the intake of undesirable metal ions in the human body. In this project, by constructing recombinant plasmids ArsD, ArsR and ArsA, using Escherichia coli and Bacillus metal-responsive promoters, the sensitivity of biosensors is detected by the intensity of fluorescent signal, and the concentration of metal ions in the sample is displayed. This project can be used to detect heavy metals, provide warnings to people, and reduce their health damage to the human body.